Brandi Carlile's new supergroup the Highwomen were revealed to be the mysteriously billed act "♀♀♀♀: The Collaboration" at the Newport Folk Festival over the weekend, and they added a special guest to their already star-studded lineup — Dolly Parton.

The country icon joined Carlile, Maren Morris, Amanda Shires and Natalie Hemby during their set on Saturday (July 27), performing some of Parton's biggest hits. She ran through "Jolene," "Just Because I'm a Woman" and "Eagle When She Flies" with the Highwomen, as well as performed "I Will Always Love You" with Carlile.